Malaria is a re-emerging infectious disease that is spreading to areas where it had been eradicated, such as Eastern Europe and Central Asia. To avoid the mortality from malaria, early detection of the parasite is a very important issue. The peripheral blood smear has been the gold standard method for the diagnosis of malaria infection. Recently, several other methods have been introduced for quantitative detection of malaria parasites. Real time PCR that employs fluorescent labels to enable the continuous monitoring of PCR product formation throughout the reaction has recently been used to detect several human malaria parasites. 18S rRNA sequences from malaria parasites have been amplified using Taqman real time PCR assay. Here, a SYBR Green-based real time quantitative PCR assay for the detection of malaria parasite-especially, Plasmodium vivax - was applied for the evaluation of 26 blood samples from Korean malaria patients. Even though SYBR Green-based real time PCR is easier and cheaper than Taqman-based assay, SYBR Green-based assay cannot be used because 18S rRNA cannot be specifically amplified using 1 primer set. Therefore, we used DBP gene sequences from Plasmodium vivax, which is specific for the SYBR Green based assays. We amplified the DBP gene from the 26 blood samples of malaria patients using SYBR Green based assay and obtained the copy numbers of DBP genes for each sample. Also, we selected optimal reference gene between ACTB and B2M using real time assay to get the stable genes regardless of Malaria titer. Using selected ACTB reference genes, we successfully converted the copy numbers from samples into titer, ${\sharp}$ of parasites per microliter. Using the resultant titer from DBP based SYBER Green assay with ACTB reference gene, we compared the results from our study with the titer from Taqman-based assay. We found that our results showed identical tendency with the results of 18S rRNA Taqman assay, especially in lower titer range. Thus, our DBP gene-utilized real time assay can detect Plasmodium vivax in Korean patient group semi-quantitatively and easily.
Park, Hyeon-Kwan;Yu, Young-Kwon;Kim, Kyu-Sik;Lim, Sung-Chul;Kim, Young-Chul;Park, Kyung-Ok
Tuberculosis and Respiratory Diseases
/
v.50
no.2
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pp.158-170
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2001
Background : Although an oxidants and antioxidants imbalance has been considered in the pathogenesis of chronic obstructive pulmonary disease (COPD), there is a paucity of reports focussing on the smoking-induced changes of oxidants and antioxidants in COPD. Method : The concentration of antioxidants (ascorbic acid, uric acid, retinol, and $\alpha$- & $\gamma$-tocopherol) was measured in the serum and induced sputum of 30 healthy controls and 34 stable COPD patients using high performance liquid chromatography (HPLC). The inhibition of lipid peroxidation as an index of antioxidant capacity was measured in the serum by a TBA assay. Results : The serum concentration of ascorbic acid, $\alpha$-tocopherol, and retinol were significantly lower in the patients with COPD than in healthy controls ($484.8{\pm}473.3$ vs $1497.8{\pm}819.2\;pmol/L$, $48.38{\pm}17.34$ vs $73.96{\pm}26.29\;pmol/L$, p<0.001, and $9.51{\pm}8.33$ vs $15.01{\pm}5.88\;pmol/L$, p<0.05, respectively, mean$\pm$SD). However, there were little differences in the ascorbic acid and uric acid concentrations in the induced sputum between the COPD patients and the controls. The induced sputum to serum ratio of ascorbic acid was significantly higher in COPD patients compared with healthy control (0.375 vs 0.085, p<0.05). In the normal controls, the serum ascorbic acid concentration was lower in smokers than in nonsmokers ($1073{\pm}536$ vs $1757{\pm}845\;pmol/L$, p<0.05), but the level was still higher than that of the COPD patients (p<0.05). The serum retinol levels were correlated with $FEV_1$ in COPD patients (r=0.58, p<0.05). The products of lipid peroxidation were increased in normal smokers and COPD compared with norma1 nonsmokers ($115.56{\pm}19.93$ vs $120.02{\pm}24.56$ vs $91.87{\pm}20.71\;{\mu}mol/{\mu}mol$ Pi of liposome, p<0.05). Conclusion : Cigarette smoking may induce the dep1etion of serum antioxidants and this depletion of antioxidants is suggested to play a role in the pathogenesis of COPD.
Background: Osteopontin (Opn) is recognized as an important adhesive bone matrix protein and a key cytokine involved in immune cell recruitment and tissue repair and remolding. However, serum levels of osteopontin have not been evaluated in patients with chronic obstructive pulmonary disease (COPD). Thus, the aim of this study was to evaluate and compare the serum levels of osteopontin in patients experiencing COPD exacerbations and in patients with stable COPD. Methods: Serum samples were obtained from 22 healthy control subjects, 18 stable COPD patients, and 15 COPD with exacerbation patients. Serum concentrations of osteopontin were measured by the ELISA method. Results: Serum levels of osteopontin were higher in patients with acute exacerbation than with stable COPD and in healthy control subjects ($62.4{\pm}51.9ng/mL$, $36.9{\pm}11.1ng/mL$, $30{\pm}11ng/mL$, test for trend p=0.003). In the patients with COPD exacerbation, the osteopontin levels when the patient was discharged from the hospital tended to decrease compared to those at admission ($45{\pm}52.1ng/mL$, $62.4{\pm}51.9ng/mL$, p=0.160). Osteopontin levels significantly increased according to patient factors, including never-smoker, ex-smoker and current smoker ($23{\pm}5.7ng/mL$, $35.5{\pm}17.6ng/mL$, $58.6{\pm}47.8ng/mL$, test for trend p=0.006). Also, osteopontin levels showed a significantly negative correlation with forced expiratory volume in one second ($FEV_1$%) predicted in healthy controls and stable COPD patients (r=-0.389; p=0.013). C-reactive protein (CRP) was positively correlated with osteopontin levels in patients with COPD exacerbation (r=0.775; p=0.002). Conclusion: The serum levels of osteopontin increased in patients with COPD exacerbation and tended to decrease after clinical improvement. These results suggest the possible role of osteopontin as a biomarker of acute exacerbation of COPD.
The primary objective of this study was to examine the toxic effects of PCP on activated sludge and to analyze its metabolic responses while treating wastewater containing pentachlorophenol (PCP) in a sequencing batch reactor (SBR) system operating under different control strategies. This study was conducted in two phases 1 and 2 (8-hr and 12-hr cycles). Each phase was operated with two control strategies I and II. Strategy I (reactor 1) involved rapid addition (5 minutes to complete) of substrate to the reactor with continuous mixing but no aeration for 2 hours. Strategy II (reactor 2) involved adding the feed continuously during the first 2 hours of the cycle when the system was mixed but not aerated. During both phases each reactor was operated at a sludge age of 15 days. The synthetic wastewater was used as a feed. The COD of the feed solution was about 380 mg/L. After the reference response for both reactors was established, the steady state response of each system was established for PCP feed concentrations of 0.1 mg/L, 1.0 mg/L, and 5.0 mg/L in SBR systems operating on both 8-hr and 12-hr cycles. Soluble COD removal was not inhibited at any feed PCP concentrations used. At 5.0 mg/L feed PCP concentration and in SBR systems operating on phase 2, the concentrations or ML VSS were decreased; selective pressure on the mixed biomass might be increased, narrowing the range of possible ecological responses; the settleability of activated sludge was poor; the SOURs were increased, showing that the systems were shocked. Nitrification was made to some extent at all concentrations of feed PCP in SBR systems operating on phase 2 whereas in SBR systems operating on phase 1 little nitrification was observed. Then, nitrification will be delayed as much as soluble COD removal is retarded due to PCP inhibition effects. Enhanced biological phosphorus removal occurring in the system operating with control strategy I during phase 1 of this work and in the presence of low concentrations of PCP was unreliable and might cease at anytime, whereas enhanced biological phosphorus removal occurring in the system operating with either control strategy I or II during phase 2 of this work and in the presence of feed PCP concentrations up to 1.0 mg/L was reliable. When, however, such processes were exposed to 5.0 mg/L PCP dose, enhanced phosphorus removal ceased and never returned.
The main purpose of this study is to describe the different life chances among various occupational groups in Chonbuk Province which has been excluded in the process of Korea's industrialization since the 1960s. More specifically, this study analyzed to what extent 6 occupational groups have the different life chances in the sub-levels such as health conditions and leisure life. According to our data analysis, it is found that the 6 occupational groups have the different life chances. That is, while those who are engaged in the higher prestigious occupation have a good life chance, those who in the lower prestigious occupation have a worse life chance. For example, among 6 occupational groups, professional-managerial who secure the higher autonomy and stability in their work have the highest life chance in the labor and health, and leisure life. Next, professional-technical, white-collar, sales-service occupants have the higher life chance after the professional-managerial. However, these 3 occupation groups are partially inconsistent in the two sectors of the life chance. Specifically, the professional-technical, despite their autonomy and stability in the work world, conceived that their work conditions are worse as well as badly influencing on their own health. On the other band, the sales-service workers group, despite their lower social status, is relatively autonomous and stable in their work environment and thus has the higher life chances. Finally, agricultural and productive workers have relatively the lower lift chances. Nevertheless, there are some clear differences among these 2 occupational groups. That is, the farmers have relatively the higher life chances in the sectors of socio-economic characteristics, and labor and health rather than productive workers. As a result, the productive workers are generally located in the lowest level of life chance. This fact is particularly attributed to the fragility of manufacturing industries in Chonbuk Province.
$SiO_2{\cdot}B_2O_3$ was prepared by trimethylborate (TMB)/tetraethylorthosilicate (TEOS) mole ratio 0.01 at $800^{\circ}C$. PDMS[poly(dimethysiloxane)]-$SiO_2{\cdot}B_2O_3$ composite membranes were prepared by adding porous $SiO_2{\cdot}B_2O_3$ to PDMS. To investigate the characteristics of PDMS-$SiO_2{\cdot}B_2O_3$ composite membrane, we observed PDMS-$SiO_2{\cdot}B_2O_3$ composite membrane using TG-DTA, FT-IR, BET, X-ray, and SEM. PDMS-$SiO_2{\cdot}B_2O_3$ composite membrane was studied on the permeabilities of $H_2$ and $N_2$ and the selectivity ($H_2/N_2$). Following the results of TG-DTA, BET, X-ray, FT-IR, $SiO_2{\cdot}B_2O_3$ was the amorphous porous $SiO_2{\cdot}B_2O_3$ with $247.6868m^2/g$ surface area and $37.7821{\AA}$ the mean of pore diameter. According to the TGA measurements, the thermal stability of PDMS-$SiO_2{\cdot}B_2O_3$ composite membrane was enhanced by inserting $SiO_2{\cdot}B_2O_3$. SEM observation showed that the size of dispersed $SiO_2{\cdot}B_2O_3$ in the PDMS-$SiO_2{\cdot}B_2O_3$ composite membrane was about $1{\mu}m$. The increasing of $SiO_2{\cdot}B_2O_3$ content in PDMS leaded the following results in the gas permeation experiment: the permeability of both $H_2$ and $N_2$ was increased, and the permeability of $H_2$ was higher than $N_2$, but the selectivity($H_2/N_2$) was decreased.
In this study we measured the amount of light energy that was projected through the tooth material and analyzed the degree of polymerization by measuring the surface hardness of composites. For polymerization, Optilux 501 (Demetron, USA) with two types of light guide was used: a 12 mm diameter light guide with 840 nW/$cm^2$ light intensity and a 7 mm diameter turbo light guide with 1100 nW/$cm^2$. Specimens were divided into three groups according to thickness of penetrating tooth (1 mm, 2 mm, 0 mm). Each group was further divided into four subgroups according to type of light guide and curing time (20 seconds, 40 seconds). Vickers' hardness was measured by using a microhardness tester. In 0 mm and 1 mm penetrating tooth group, which were polymerized by a turbo light guide for 40 seconds, showed the highest hardness values. The specimens from 2 mm penetrating tooth group, which were polymerized for 20 seconds, demonstrated the lowest hardness regardless of the types of light guides (p < 0.05). The results of this study suggest that, when projecting tooth material over a specified thickness, the increase of polymerization will be limited even if light intensity or curing time is increased.
Persimmon (Diospyros kaki. cv. Fuyu) fruits were packaged under different conditions, and then stored at $0^{\circ}C$ for 21 weeks. The tried packages were heat-sealed bag of one fruit, heat-sealed bag of five fruits, and tie-sealed bag of five fruits, which used films of three different thickness (0.03 ㎜, 0.05 ㎜ and 0.06 ㎜). Throughout the storage, package free volume, package atmosphere and quality were measured. Package free volume decreased with time with higher rate for heat-sealed bags, in which close contact between fruit and the film was eventually reached in longer storage. However, tie-sealed bags maintained the levels of stabilized free volume. The rate of free volume decrease was faster with thinner film and larger bag size for the packs sealed by the same method. Package atmosphere covered $O_2$ concentration of $1.1{\sim}17.1%$ and $CO_2$ concentration of $1.1{\sim}8.3%$, $O_2$ concentration decreased during storage, whereas $CO_2$ increased. Thinner film package created the internal atmosphere of higher $O_2$ and lower $CO_2$ concentrations. Tie-sealed bags of 5 fruits in the films of 0.05 mm and 0.06 mm thickness maintained the equilibrated package atmosphere of $1.1{\sim}3.0%\;O_2$ and $4.0{\sim}5.5%\;CO_2$, which preserved the fruits best in terms of firmness and less physiological changes of flesh browning and peel browning. At five fruit heat-sealed bag in the films of 0.06 mm thickness with $CO_2\;8.3%$, flesh browning occurred at a high rate, whereas all treatments in the film of 0.03 mm thickness with high $O_2$ and relatively low $CO_2$ contents, flesh and peel browning rates were high.
The purpose of this study was to investigate the effects of onion and garlic juice on the lipid oxidation of fish oil as antioxidants and quality characteristics of fish muscle. The samples were treated with onion and garlic juice at 5%(w/w) or 10%(w/w) of fish muscle, and stored at 4$\pm$1$\^{C}$ and -18$\pm$2$\^{C}$ for 7 and 42 days, respectively. The results of this study were as follows: Lipid oxidation in samples was measured by AV, POV and TBA value. AV and TBA values of the samples treated with 5% onion and garlic juice were lower than those treated with l0% onion and garlic juice. POV of the samples treated with onion were lower than those treated with garlic juice. Lightness and yellowness of the sample were the highest in 10% onion and garlic juice-treated ones. The score of overall quality in sensory evaluation was the highest in the samples treated with onion juice stored at 4$\pm$1$\^{C}$.
Journal of the korean academy of Pediatric Dentistry
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v.27
no.4
/
pp.505-516
/
2000
Chloral hydrate is one of the most widely used sedative agents to control the difficult-to-treat young age group in the dental clinic. We are often frustrated to see the patient still awake and cry with agitation even after far more than the normal onset time of Chloral hydrate. In such a case, the patient has to be rescheduled for another sedation visit with different agents and/or routes which greatly disappoints the guardians. This study was designed to test the efficacy of one sedative regimen that can possibly help the clinician complete scheduled treatment without postponement. We have tried sleep induction with mixed gas of Enflurane(2vol%) and $N_2O(50%)-O_2(50%)$ for $60\sim120$ seconds to 35 patients of those who failed to respond properly to the dose(70mg/kg)of oral Chloral hydrate. The Result of this regimen was compare to those of two oral regimen of Chloral hydrate/Hydroxyzine and Chloral hydrate only Analyses of result on vital signs and behavior pattern were performed. The outcome of the study suggest that sleep induction by a short inhalation of low dose of $Enflurane/N_2O-O_2$ provide dentist with suitable condition for the completion of scheduled treatment in the patient who failed to oral Chloral hydrate. Evidence of adverse effect was not detected or reported during and/or after the procedures.
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